Humorously mocking (3)
I believe the answer is:
wry
'humorously mocking' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for wry that I've seen before include "Of humour, humorous and mocking" , "Of facial expression, mocking or twisted" , "Drily humorous" , "Of humour, dry and mocking" , "Twisted out of shape like facial expression" .)